The new NICE guidance on asthma diagnosis and treatment has received a mixed reaction from respiratory specialists in both primary and secondary care. As a respiratory-interested GP and a secondary care specialist in respiratory medicine, we appreciate the commitment from NICE towards improving asthma management.
However, the fact is we already have an up-to-date set of recommendations from BTS/SIGN, for years the trusted source of gold-standard clinical guidance on asthma. NICE’s intervention means we now have two distinct sets of national guidelines that differ on crucial diagnostic and treatment recommendations. We believe this will only serve to confuse both GPs and secondary care specialists, and could even lead to patients receiving suboptimal care.
Both guidelines emphasise the importance of diagnosis, correct treatment and regular review, which we like to sum up under the acronym ‘DREAM’:
- Diagnosis – get it right, first time if possible, and document your rationale;
- Register – stratify according to severity, risk;
- Education – of both patients and practitioners, giving consistent messages, guided self-management;
- Appropriate treatment – for diagnosis and severity of disease, personalised
- Monitor – conduct a regular, structured review, document findings and changes.
However, the guidelines diverge in three crucial areas:
1. Firstly, the diagnostic algorithm in BTS/SIGN 2016 guideline divides patients into three groups depending on clinical suspicion of asthma diagnosis. Put simply: if a high probability of asthma, give a trial of inhaled steroids; if a low probability, consider other diagnoses; if intermediate probability, perform objective tests like spirometry, reversibility and FeNO.
By contrast, NICE’s 2017 guidance advises us not to make a diagnosis at all without a confirmatory test. It has developed complicated algorithms focusing on measures of airflow obstruction, airways inflammation and hyper-responsiveness for all patients, from the age of five, and suggests development of specialist ‘diagnostic hubs’ to support this.
2. BTS/SIGN no longer supports use of a short-acting beta-2 agonist (SABA) alone, and advises use of an inhaled corticosteroid (ICS) as first-line treatment. This was a watershed change in the 2016 update, helping patients and clinicians alike understand that preventive steroid therapy is now considered the definitive treatment for all patients. NICE, however, still recommends SABA alone for some patients.
3. NICE also reverses the place of leukotriene receptor antagonists (LTRAs) and long-acting beta-2 agonists (LABAs) as add-on therapy to ICS, suggesting an LTRA before LABA. This is because they have examined the evidence from a cost-effectiveness as well as a clinical effectiveness point of view, and recommend trying an LTRA first when stepping up therapy, despite acknowledging that LABA is more clinically effective.
So, how can GPs make sense of these, and other differences?
Getting the diagnosis right matters, everyone agrees on this point. But the divergence in guidance on diagnosis reflects two main schools of thought that currently divide experts.
The first, echoed by BTS/SIGN, maintains that asthma is a clinical diagnosis for which there is no single, black and white, binary test result, although objective measures can help where there is diagnostic doubt on clinical grounds alone.
The other, channelled by NICE, holds that diagnosis of wheeziness should be treated in the same way as chest pain, considered a serious symptom with the potential to kill. All patients should be referred to a diagnostic hub (akin to a rapid access chest pain clinic) for a series of objective tests to obtain a definitive diagnosis from specialists.
In our view, the diagnostic hub approach is not supported by the balance of evidence. For one thing, asthma is inherently variable; for example, a normal response on objective testing at one point in time cannot exclude asthma in the face of typical symptoms.
It is also highly doubtful that objective tests are needed for every diagnosis. What about the wheezy atopic child with a strong family history of asthma who improves with a trial of inhaled corticosteroids?
The practicalities of this approach are also hugely challenging, considering one in 12 adults suffers from asthma. Findings from NICE’s own ‘implementation feasibility’ study were, at best, mixed, with no clear steer on the relative success or cost-effectiveness of community diagnostic hubs or secondary care led models.
There is also a risk of mass de-skilling of the GP workforce if asthma diagnosis becomes a specialist activity. How will GPs assess treatment response, or deal with managing exacerbations? We need more evidence before committing to such an overhaul.
Regarding treatment, we believe it is vital to keep promoting the message that preventive medication for the underlying inflammatory condition is central to successful asthma control. BTS/SIGN emphasises this by recommending ICS as a first line treatment for asthma, whereas NICE’s advice takes us back to the thinking that ‘it’s OK to treat mild asthma with a SABA alone’. SABA inhalers should only be used as reliever medication in any patient and we should monitor their use closely, as over-use may enhance airways irritability. The National Review of Asthma Deaths showed us that failure to use ICS effectively contributes to asthma deaths, with 13% of all deaths occurring in people treated with SABA alone because their asthma was considered mild enough to not need ICS.
Meanwhile NICE’s substitution of LTRAs for LABA risks poorer adherence to mainstay steroid therapy, as it means asking patients to take both a regular inhaler and a tablet, instead of one combination inhaler. There are also potential increased costs for some patients – given that a combination ICS/LABA inhaler incurs one prescription charge whereas using LTRA and ICS incurs two.
GPs are now faced with a choice to follow NICE, or BTS/SIGN, or pick and choose which bits of both they like. Unless we sort this out, the danger is that some will view the situation as sufficiently confusing to justify abandoning both.
We would encourage GPs to consult this excellent consensus statement from the UK Primary Care Respiratory Society, based on their briefing document which highlights both similarities and differences between BTS/SIGN and NICE asthma guidelines, and advises how to proceed where there are discrepancies. There is also a helpful article by the British Thoracic Society.
Both articles lay out the key information for clinicians to judge themselves. We feel they are sensible, well written and pragmatic.
It is also important for us to learn from this misadventure. It cannot make sense that NICE and BTS/SIGN did not work together to produce one strong set of guidance which, while pointing out where evidence is strong or lacking, comes to a single consensus on diagnosis and treatment of asthma. In future we must involve professional and patient organisations and strive for consistent, best patient care.
Surely the least all of us, specialist or not, can expect from expert bodies is to work together to give us clear, evidence based, practical guidance.
Dr Stephen Gaduzo is a GPSI in respiratory medicine in Stockport; Dr Binita Kane is a consultant chest physician and lead for integrated respiratory care in Manchester